As I argued with a German consultant over the word “bi-weekly” it became clear to me that German Business English is a dialect with its own conventions and standards, as different from British English as Australian say.
In this case, the consultant was not prepared to put the word “fortnightly” into his document as it was not a word with which he was familiar. I explained that “bi-weekly” is ambiguous - it can mean “twice a week” just as easily as it can mean “every two weeks”. However its usage in German Business English appears to be entrenched.
I’m not saying this is a bad thing. Living dialects are part of the beauty of the English languages. It just means I need to start mentally translating just as we do when talking to Americans.
More examples when I come across them. Have you noticed any?